1. Field of the Invention
The invention relates to a power supplying device, and more particularly, to a power supplying device having coils.
2. Description of Related Art
In the conventional art, a power supplying device having coils is proposed (e.g., referring to Patent Document 1).
In Patent Document 1, a wireless power device having a first primary coil, a second primary coil and a differential driving amplifier is disclosed. Each of the first primary coil and the second primary coil is in a planer shape and wound into a spiral shape. Further, the first primary coil and the second primary coil are connected to the differential driving amplifier, and grounded at a position further outside than outermost windings of the first primary coil and the second primary coil. Also, the power supplying device is configured to make the first primary coil and the second primary coil generate electric fields with different polarities through the differential driving amplifier and make the first primary coil and the second primary coil generate magnetic fields with the same polarities for power supplying. As such, in the power supplying device of Patent Document 1, the magnetic fields for power supplying may be generated under the circumstance where the electric fields with different polarities generated by the first primary coil and the second primary coil are canceled by each other when viewing from afar.